The Soul Thief
by Jack O The Lantern
Summary: You're never alone if those who proceeded you mark your path. Their mistakes, triumphs, friends... the Underground is a dangerous place, but a guide can make all the difference. How can you steal something that refuses to leave you? That comes to you? That grows to love you? Rated T for Taking this thing seriously. Based on the original game. Spritetale. Plz review if you enjoy.
1. Chapter 1

I'd like to say a few things…

Firstly, this is not an AU. Not really.

This is something called a Special Event AU. Basically, all of the characters are the same, but the story is different because of one event that wasn't canon.. One singularity, or I should say, one _theft,_ changed the course of the Tale Under the Mountain. Going forward, you won't need to know much if you've already played Undertale. (If you haven't, um… well, I don't know why you're here, but you're welcome to join us. I won't stop you from reading. But maybe go watch a playthrough or something. Or just get the game. It's not too pricey.)

Feel free to skip this little rant if you want. Just go to the beginning of the story.

No? Curious? Bored? OK, you asked for it.

A pet peeve of mine has always been reading Undertale Material about Frisk where authors refuse to pick a fricking pronoun. (or is it Frisking pronoun?) The whole point of Toby Fox making Chara and Frisk unambiguous was so players of both genders could fully insert themselves into the story; the same reason why Frisk never talks, like Red in the first Pokemon game.

That said, I don't think amateur authors do this well. They don't make Frisk gender-neutral to appeal to a diverse audience, they do it to stay true to some imaginary canon. Well, here's the real canon- yes, the game doesn't tell us if Frisk is a gal or a guy, but they ARE one of the two, SO PICK ONE GUYS! I'm sick of people using the words 'they' and 'them' to mean one person rather than a group. It's a plural pronoun, and, I'm sorry, I love this franchise, but not enough to murder grammar itself. I'm an author for crying out loud. Such an atrocity I cannot stand for. I'm not perfect- I'll have the occasional typo, but I won't intentionally maim English.

Now, if you've written stuff about Undertale and played the they/them game, I don't hate you. You're just doing what other authors have been doing ever since we fans started writing about Undertale. And those first authors didn't have malicious intent either; they were just trying to make the writing more like the game. But in analyzing the game, I think they lost a part of the game that is unique to each of us. Our experience.

Go ahead, keep playing the pronoun game. I've come to accept that it's just part of the norm. But please, consider actually giving Frisk some identity. Put a little of yourself into him/her, or maybe a little of someone you know. Frisk doesn't talk much because that makes it easier for us to feel like _we_ are Frisk. Go ahead, make him/her say something.

That said, please don't hate me or refuse to read my story when I tell you that I made Frisk a dude.

Firstly, I'm a guy, so it made sense to me. And secondly, I feel like when Frisk and Chara aren't "theys" they're always "hers". (That sentence was weird. Lets try again.) If not stiffs, the two of them are always female.

Rest assured, this story will have plenty of kick-butt ladies taking center stage, and I don't just mean Undyne. Have an open mind, girls.

Now, I'd love to stay and chat, but there's a young man running for his life up the slope of Mt. Ebott, and he requires my attention. (By which I mean I'm going to shove him off a cliff.) On with the show.


	2. Chapter 2

On the winds of chance

Long ago, two races ruled over the earth: humans, and monsters.

One day, war broke out between the two races. After a long battle, the humans were victorious. Using powerful magic, they sealed what remained of monsterkind underground.

And then came the battle of time.

With time, monsters became the stuff of human's bedtime stories. The humans forgot about their ancient foe.

The monsters could not forget the humans, for they were their jailers.

With time, the humans put aside the simple beauty of magic for the complexity of machinery and smoke. Wood and stone gave way to metal and fire.

The monsters could not put aside magic, for magic was what held them prisoner.

In the battle of time, it was difficult to declare a victor, or a loser. Who could say whether it was the humans or the monsters who had triumphed over their common enemy?

Remembrance? The lack of memory? Where is the virtue in either?

Either way, Time always wins.

-}&{-

Underneath a castle of dark stone, six glass cylinders were found shattered and empty.

A letter sealed with a royal crest arrived at the home of two brothers, nestled in the middle of a snowy wood.

The tines of a three-pointed spear, dulled by neglect, sparked against a grindstone.

And up the slopes of a dark mountain, a young man ran headlong into a forgotten world.


	3. Chapter 3

I am attacked by a buttercup.

It's difficult to describe the feeling, but I'll do my best.

Have you ever laid down next to someone, and without touching them, felt them there? Maybe it's the way a mattress moves when they shift around, or the sound of the grass as they stretch out and yawn. There's this electric feeling, as if the space between your body and theirs is charged. This usually works best with someone who is not an immediate family member, though I'm not sure why. I _would_ say it's because there's something alarming about the closeness of a stranger, but actually, it works best with a friend or significant other. I don't want to think too hard about it, though. One of the things that makes it special is that I can't understand it.

Unlike falling thousands of feet to what _should_ have been my death, but wasn't. Even after I understood how I survived, that was still special.

For starters, the flowers broke my fall. That one was painfully obvious; obvious because I was lying in them facedown, and painfully so because I was wracked in more pain then I'd ever experienced. I couldn't stand, I couldn't turn my head, it was all I could do to twitch.

Of course, had I fallen straight down onto the flowers, I still would have died. As it was, it had been so long since someone had been dumb enough to fall down the hole that mineral deposits had grown across the span on several different levels. Over time, dirt and brush had fallen down, landing on the plates of mineral and making them thicker. As I'd fallen, I'd hit several in succesion. Each one had shattered, and the successive impacts had slowed me down. Of course, I wouldn't piece this together until later. All I knew right then was, there had been other floors before this one, and I'd gone straight through them all.

It might've been a ridiculous series of coincidences and dumb luck, but in the moment I didn't question it. It seemed to me that if the universe was going to put me through something so traumatic and painful, the least it could do was let me live.

My mind told my body to push itself up and look around.

But it refused.

So I lay in the sickly sweet smell of flowers and whatever muted moonlight was filtering through the brand new hole I'd punched in the mineral deposits overhead.

I was preparing to make a second attempt at getting up when it happened. I suddenly felt the presence of someone lying beside me in the flowers. I held my breath, but couldn't hear their breathing. I thought about what to say, but the words would not come. I decided to say something anyway, but my throat constricted. I was being held in the tension and the silence by some part of me that I did not understand.

I fell asleep lying beside them, without knowing a single thing about them.

-)o(-

 _Get up._

I awoke to the sun. It came in hesitant shafts, as if unsure whether it would be welcome in this new place.

I knew the feeling.

My body had apparently declared a truce, as I sat up with little effort. I saw the impression my body had pressed into the flowers. I decided not to notice the second print of a figure lying on its side inches from me. It was facing towards where I had lay, and was about as long as me. But of course I didn't notice this, as I had decided not to.

It was an odd sort of cave. The ceiling was pitted with holes, and underneath the ones that shone sunlight, patches of buttercups sprouted in waving herds. In some places, a hole had been covered up, leaving a patch of dead flowers.

Craning my neck, I gazed up at the way I'd fallen. I could see the sun. That was about it.

I found shards of mineral in the green stems and started to piece together the miracle of my survival. It was clear I wasn't getting up the way I'd come, and I started to wonder how long I would be a cave hermit. On the bright side, if it ever became too much, I could just eat a buttercup and end it all.

 _"Well, that's a little macabre,"_ I thought to myself, strolling through the cave. I didn't have much of a direction in mind; my feet seemed to know where to go. I admired the way the green and yellow turned from bright to shady, like an ocean's tide made of light.

I wasn't sure why it scared me so much. There were plenty of flowers in this place. If one slightly larger flower came shooting up out of the earth, in a patch of grass devoid of any other flowers, what did that matter?

 _Careful._

I crept forward, unsure as to why I felt such dread. Until the face of the flower turned towards me, and it turned out it had an actual FACE.

It was simple, honest, and open. Just two eyes and a smile, carefree as the breeze.

 _Watch yourself._

Yeah, it was freaky, but it wasn't terrifying. At least, that's what I tried to tell the voice in my head. It wasn't buying it.

 _Don't turn your back. Not even for a second._

So I didn't. I just stood there and stared at it.

"Hi there!"

I blinked. Sure, why not? It had a face, why shouldn't it talk?

"Um… hi?"

"I'm Flowey! Flowey the Flower!"

The voice was high and reedy, and should have been annoying, but for some reason, it made me think of my favorite memories of home. I felt safe and relaxed, like I should just go ahead and lower my guard…

I took it all back. I was with Voice on this one. Something was very wrong. If the botanical wonder could see my trepidation, he didn't say so.

"Suppose you tell me your name?"

"I'm… Frisk."

"Frisk, huh? Golly, that's a nice name!"

No, it wasn't. It was a stupid name, and he and I knew it. I almost shot back, _"Golly, that's a nice act! Now what do you want?"_

 _Wait. Not yet. Have_ _ **Patience**_ _. Stall a bit. Let's see how this goes…_

OK, make small-talk with the flower. Piece of cake.

"So, I uh… fell down this hole, it's like 5 minutes that way, so I wondered, is there some kinda staircase, or a ladder-"

"My my! You're _new_ to the Underground, aren'tcha! Golly, you must be so confused! Well, someone's got to teach you how things work around here. I guess little ol' me will have to do."

 _The branch. Don't look at it, or he'll see it too. It's over to the left, a little ways in front of you._

I willed myself to not look, and focus on something else, like the weird look in Flowey's eye, or how much I hated the word 'golly'. Flowey was doing something strange, screwing up his eyes in concentration. Just when I was starting to worry, a light, like a crimson flame, burst into existence before me.

It was a heart. Not a blood pumping, hard pounding organ. Thankfully, _that_ thing was still inside of me. This was a valentine, a love note, the most sinister of playing cards. It bobbed and spun, leaking red light. Bright like a traffic signal, dark like still blood. I couldn't take my eyes off it. It was easily the most beautiful thing I'd ever seen.

Flowey laughed. "You've never seen that, have you? That's a Sprite, the physical manifestation of your Soul. Your Soul is the very culmination of your being! Everyone has a Soul, and down here souls… well um, they're very, sort of…."

Flowey trailed off, a curious look coming over him as he gazed at the Sprite. Something dangerous was stirring inside those eyes. "Well, would'ja look at that," he murmured softly. "That looks _exactly_ like..."

He looked up with murder in his smile.

 _Crap. We're in trouble. Dive!_

I took a leap to my left, and as my hands found purchase, they grasped something hardy and stubborn. I rolled and came up holding a crude stick, about as long as my arm, from fingertip to shoulder. I turned to face Flowey.

His face was a nightmare. His mouth, the _teeth_ , the look in his eyes…

He cackled. "I really **am** an idiot! Why didn't I see it? Long time, Chara! So, back in the saddle, then? Time for another round of Genocide?"

Green vines burst from the ground, darting at my face and chest. As I swung the branch into the low shot, my head dodged the high one on its own. _Frisk, listen to me. If you hesitate, if you let one thing he says get to you, we are as good as dead. We don't have the luxury of mistrust right now. We nee-_ _MOVE_ _!_

A hailstorm of white bullets shot down from the flower. He seemed to make them out of thin air; a problem, as that meant he might never run out.

I broke into a run as the ground behind me was peppered in buckshot. A vine rose from the dirt, and I swung the rod. As I struck, I saw Flowey flinch in my peripheral.

Voice noticed as well. _So, he can feel through these things._

To give context as to how weird the next part, you need to know that I was never much of a gymnast. I pretended to know parkour, but I'd never so much as done a backflip on a trampoline. So when I vaulted a pair of grasping vines with a flip-pivot, I was more than a little disoriented. I almost fell over, but stuck the landing.

 _Don't worry about dodging. I'll watch his attacks, you figure out how get me in close._

I leaped back as white darts hit the ground in front of me, then dashed towards the flower. I tried to run while keeping low to the ground, leaning forward into the movement. A bullet grazed my shoulder. I tried to push through the sting, hoping he would make his mistake.

It worked. As I drew close, another vine burst forth to block me. I felt Voice about to take over and dodge, and thought desperately, _Jump up!_

It worked. Rather than avoid the vine, when my body acted on its own, it did what I needed it to do. I sprung atop the appendage. Before the flower could work out what had happened, I brought the branch down on the vine.

"OW! Golly, I'm going to kill you!"

 _NOW! Hit him now!_

I jumped, swinging at the Flower, who was distracted by the pain.

I missed. He vanished under the soil just as my weapon got to him, like a really scary whac-a-mole.

The vines retreated as well, and the pellets stopped, so I guessed I was- _we_ were in the clear. I took a breath and sat down on the grass, trying to cope with the exhilaration of battle, the sensation of losing control of my body, and the sting in my shoulder. I was also exhausted, and the fact that I had a voice in my head that told me how to win was finally catching up to me.

"Wowie! That was quite the performance!"

I stood up as if I'd been burned. Whirling around with my branch held ready, I saw no sign of the freak. His voice seemed to come from the earth, but with echo of the cave, it was hard to tell.

"You must be really happy with this one, Chara! Quite the fighting spirit. If he's as good as all that, it's only a matter of time before everyone is nice and dead again, just the way I like them."

I clenched my fists. I didn't know what he was talking about, but I didn't like this guy one bit. The voice in my head made no comment.

"Y'know, I thought this timeline was gonna be boring, but tha'jus goes ta show ya! Next thing I know, all six have been stolen, an' Asgore's got 'is best runnin' from here to Hotland lookin for the thief! Then this guy shows up. Man, you really got the angry look _down,_ don'tcha, stripes?"

OK, that was going too far. Trying to kill me was one thing, but this was low. I liked my hoodie. "Pretty rich, coming from the guy who can't wear any clothes! Besides maybe a funny hat."

The flower just laughed. "Oh, man, his comebacks need some work, but golly, this guy's got some guts! _Finally._ Up to now, we haven't had anyone fall down who wasn't a total wuss!"

 _Don't encourage him. The sooner he gets bored and leaves, the better._

"Well, except maybe Harrison, but that guy was a real moron. I mean, can you think of a dumber way to die than going and-"

He cut off then. I wasn't sure why, until _she_ came over the hill.

It really wasn't so surprising. At least, not in that moment. The trend had seemed to be that if you didn't think about it, you could move on. So I just accepted the fact that the goat lady was a goat lady and focused on something else.

She wore a purple dress with a strange, silver crest on it. She had shiny white fur, and a concerned look on her face. Her path was lit by the fireball she held in one hand. (Again, I just rolled with it.)

 _There she is. Don't worry, she'll help you._

I had a feeling I was gonna need to get my head checked, eventually. I sat down hard in the grass, my pleading look meeting the disbelieving wonder of the woman who would be my mother.


	4. Chapter 4

We meet the Bookworm

Brussel sprouts, man. They get all the hate. I mean, why though? You ever tried 'em roasted with a little garlic and lemon? I get hungry just thinking about it. Truth is, most any food is a delicacy if you go about it the right way. I say _most_ any because, sadly, this does not apply to snails.

Now I know the French have that Es-car-go thing, but I'm not talking about French snails, I'm talking about cave snails, and let me tell you friend, cave snails… _yeugh._

Not that Mom didn't do her best. She really tried. But to be honest, you might get used to them, but they'll never grow on you. I did my best to get on with some bread and cheese for breakfast, knowing that I would have to face snail-turnover for lunch. But dinner was the real treat. Not the snail stew, but what came after…

 _What-came-after_ was the reason I was hovering in the tidy little kitchen, dodging Toriel and generally making a nuisance of myself. She laughed as I danced around her, swatting at me with a wooden spoon. "Out, you little urchin! It'll never be done if you hang about!"

"Then I'll smell this heavenly aroma for all eternity."

"Oh, no you won't! Not in my kitchen!"

She finally managed to chase me out, and I chuckled to myself as I strolled down the hall to my room. Toriel liked to say that just my being around could make her happy, but that didn't mean I couldn't put in an extra effort.

I looked down the hallway past Mom's room to the one "under renovations", and then shook my head and pushed into my bedroom.

There was the familiar feeling of a great pull in my chest, and then a voice said,

"If you never go in that room, you'll never know the whole story."

I quickly slammed my door shut, before turning 'round, exasperated. "Do you _want_ her to find out about you?"

Chara didn't have the decency to _look_ sorry. She was perched atop the vanity, swinging her long pale legs like a little kid, reclining back against the mirror. "Do I look penitent enough?"

Nothing about her was remotely penitent. The constant ease of her pose, like a cat that was always in the Sun. Her chocolate brown eyes matched her hair, which was short and choppy, like she'd hacked at it with a knife. While her shorts barely came halfway down her thighs, her clothing from the waist up seemed overly concealing; she wore the same sweater as always, with horizontal yellow and green stripes, the sleeves hiding slender pale hands.

I sighed, annoyed. "No." I opened the old toy chest, digging around for something interesting. Most of the junk in there I'd seen countless times, but I was bored. At the bottom I found a piece of new junk; a broken toy sword. So I flopped onto the bed, waving and slashing it through the air. "You're the one who said, _'She can never know about me,'_ and yet you seem to constantly flaunt your presence. I don't… what?" I stopped, having noticed the dark look in her eye. "What'd I say? It's true, you told me-"

"You shouldn't play with that."

"This old thing? It's a toy, that's what it's for."

"No. Not that toy."

She had my attention. I sat up, turning the scrap of wood over and over in my hands. The craftsmanship that had gone into it was evident- the intricate carving and quality of the wood spoke of this. But as I ran my hand over the harmless blade, I noticed something. "This wasn't broken..."

Chara just looked at me. I thumbed the blackened edge, the sudden roughness of the surface. "This was burned. What, did someone stick it in the fireplace?"

A deep sigh, telling me there was a lot I didn't know. She picked at the hem of her sweater, the way she did when she was nervous. Or about to give me an answer. _Yes._

It had been almost a month since Toriel had taken me in. Since then, I had explored every inch of the ruins, solved every puzzle, learned hundreds of fascinating snail facts, and met the person who lived in my head. Getting her to show her physical form had taken a little less than a week- her name had been a week more. She'd given me advice, warnings, threats, and someone to talk to. She'd been an odd sort of friend, but a good one. But answers? Those she gave sparingly.

There was a flare of scarlet in her chocolate eyes.

We were in business.

"Get your stupid hoodie."

I was too happy to correct her. (It's not stupid.) I pulled on the beloved purple cloth as Chara's body faded like a dying light. I felt the warmth behind my sternum that meant she was back where she belonged. I went to step out, but stopped, grabbing the burned wooden sword from where I'd tossed it on the bed. I tucked it under my belt as I stepped into the hall. "Mom!"

"Heaven's child, if you don't stop nagging me, the pie will _never_ be done!"

"No, I'm just gonna go for a walk."

Silence. She was always hesitant when I asked. I could picture her in the kitchen, looking down and breathing slowly. I mouthed the words as she said them.

"Don't forget your phone, dear. Call if need be."

"I will. You're amazing!"

"So are you, dear! Have fun!"

From the table by the door came my black flip-phone, and from against the door-frame, my staff, right where I'd left it.

 _Why'd you take the_ _sword? It's been burned short, it's practically a toy knife._

I paused with my hand on the doorknob. I answered softly.

"Call it… a premonition."

Perseverance

I'm usually pretty good at cards, but whenever I teach Egyptian Rat Screw to someone who's never played before, they always end up being better than me. This definitely applied to Napstablook. He was incredible, no matter what slap rules I threw at him. Marriage, tens, sandwich, didn't matter. He even started making up his own rules, like 3 primes in a row, or replacing red and black suits with dots and dashes, and then trying to spell his name in morse code. It was painful for me to lose over and over, but even worse for Chara, who was trying to give me advice and instruction. She wanted to lend me her speed and reflexes, like she had when we'd met Flowey, but I didn't want to risk Blooky noticing the change. Plus, winning did his self-esteem wonders.

As my cards faded into the cytoplasm for the millionth time, I laid back on the sparse grass and purple brick. "Let's play a new game, k?"

The ghost looked at me with shifty eyes and materialized a top hat onto his head- the closest he ever came to gloating. "Aaaalright. You waaanna listen to soome muuusic?"

 _Oh please no, not another trap remix. Please, Frisk,_ _ **spare**_ _me._

I thought to Chara to shut up and tried to sound reluctant. "Actually, just remembered- I promised Toriel I would run the spike puzzle today. Any advice?"

The ghost looked indifferent.

"The spiiikes go riight throouugh me, so I neever reeally pay atteention. Sooomeone toold me, thoough, that the path doesn't generate randomly; it follows a pattern when it changes day to day, so if your numbers are right and you know what it was the day before, you can walk through with your eyes closed."

I just stared at the ghost. Napstablook didn't seem to understand that what he'd just said was a) totally out of character and b) really _really_ out of character.

 _Who. Who told him that? Ask him, ASK him._

"Where'd ya hear that?"

Napstablook looked thoughtful, then confused. "I heard it… a few seconds after you asked your question. That voice in my head. I guess you didn't hear it?"

I bid my dead friend a hasty farewell. As I strolled through the ruins, Chara took the liberty of thinking out loud. In my head.

 _A voice in his head… that's weird. I seem to remember Napstablook being weird anyway, but this is, like, MEGA weird._

I rolled my eyes. "I've been adopted by a goat after I fell down a hole I can't climb out of. I got attacked by a flower and there's a ghost living inside me who helps me play cards with _another_ ghost. Weird is the new normal, doll. Now. Answers."

I pulled the burnt sword from my belt and turned it over in my hands. "This old thing has some sort of history, and I'm thinking you know all about it."

 _His voice changed. His speech thing. He didn't linger on the vowels when he said it._

"Why are there so many sizes of shoes in my room? Why is the room at the end of the hall locked? If Toriel lives alone, why does she have a double bed?"

 _What were you doing in Mom's room?_

"And that's another thing. Why do _you_ call her Mom?"

She went quiet.

"You knew she would come for me after I fell. You knew I could trust her, after the _first person I met_ tried to kill me. I know you know what's going on, and you can't just keep me in the dark."

There was a brief silence. And then,

 _Sometimes knowing half the story is worse than not knowing anything._

I didn't have much time to think about what that meant.

Not having paid attention, I had wandered into the room with the buttons. There was a grinding noise, and the walls and columns shifted position, disorienting me. The way this room was built, you hardly had to move to lose your sense of direction. I tried to stay calm. Which phase were we in? Yellow?

 _Blue. Someone hit the button. Probably a stupid Whimsum not watching where he was flying._

My instincts told me otherwise.

I ran for a door, and the room sounded again. The door disappeared, and I was thrown backwards by a swinging section of wall. I rolled backwards, coming up with the half-sword gripped in my hand. As I knelt, panting, the room moved again. And again.

We were in trouble.

 _That was Red into Blue again, then Yellow… wait, unless that was Yellow before, in which case-_

I had a feeling I knew where this was going. Theoretically, if I had the rest of the ruins mapped out, any one of the doors could get me home. But it was impossible to use a door while the room moved, and I couldn't know where the doors would be in advance if I didn't know what buttons had been hit.

I ran at an empty section of wall. If I could reach a vantage point, I could at least see who was hitting the buttons. But a column moved to block my path as the room shifted yet again.

 _That was either Red into Yellow, or Blue into Red, I think, so if the next one is Yellow…_

"Stop. It doesn't matter."

 _Doesn't matter?_

"Just help me pull this off."

I ran as if trying to get to where I _thought_ the Yellow switch was, and as the room moved to block me, I ran straight at the wall instead of moving to avoid. My feet planted in the gray stone, and Chara took over. I vaulted back, flipping through the air towards what, for a moment, was the ground. But I had been right. The sudden move had taken my captor by surprise. Instinctively, they had hit another switch. The room shifted as I pivoted through the air, and a pillar moved under me. I landed atop it, and from my vantage point could see all three doors.

Keeping track of the phase shifts had been pointless: if one knows where all three doors are, he instantly knows what phase the room is in. We were in Blue, and now that I could see everything, he would shift to knock me off the pillar. That meant he would be at…

As the pillar under me began to move, I leaped, again trusting Chara. I stepped on and off the top of a wall as it slid by, landing right in front of the Yellow switch. I drove my burned sword up into

nothing.

Had I been wrong? Had they gone for Red?

 _Frisk, behind you!_

I didn't have a chance. I was the ultimate chump. Chara's reflexes almost saved me, so the first blow only glanced off my skull. I fell to my knees, my ears ringing, I could feel Chara trying to burst out of me, could distantly hear her screaming, and the sound filled me with Determi-

Then he hit me again, and all was dark, and quiet.


End file.
